#include "enemybullet.h"

Enemybullet::Enemybullet()
{
    //加载子弹资源
     m_Bullet.load(ENEMYBULLET_PATH);

     //子弹坐标 初始坐标可随意设置，后期会重置
     m_X = Game_WIDTH *0.5 - m_Bullet.width()*0.5;
     m_Y = Game_HEIGHT;

     //子弹状态
     m_Free = true;

     //子弹速度
     m_Speed = BULLET_SPEED;

     //子弹矩形框
     m_Rect.setWidth(m_Bullet.width());
     m_Rect.setHeight(m_Bullet.height());
     m_Rect.moveTo(m_X,m_Y);
}

void Enemybullet::updatePosition()
{
    //如果子弹是空闲状态，不需要坐标计算
    //玩家飞机可以控制子弹的空闲状态为false
    if(m_Free)
    {
        return;
    }

    //子弹向下移动
    m_Y  += m_Speed;
    m_Rect.moveTo(m_X,m_Y);

    if(m_Y <= +m_Rect.height())
    {
        m_Free = true;
    }
}
